Instrument for removing corns and callosities without danger



July 26 1932. J HQL 1,869,197

INSTRUMENT FOR Rmdvnit's coR'Ns ANDCA'LLOSITIES WITHOUT DANGER Filed Nov. 29, 1929 skilled operator.

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Patented July 26, 1932 UNITED STATES QFFICE JOSEF HOLZ, OF PFORZHEIM, GERMANY Application filed November 29, 1929, Serial No. 410,476, and in Germany December 4, 1928.

The subject of the present invention is an instrument for removing corns and callosities. As compared with the instruments hitherto used for this purpose it has the advantage that an unintended too deep penetration of the cutting edges is prevented and thus injury to the patients avoided so that the instrument permits of removal of corns and the like without danger even by a less A further advantage is that the tool bearing and protecting head is of minimum size so that it does not hide the field of operation when working.

This advantage is secured by the fact that the cutting edges of the rotating tool body are mounted in enclosed form in the tool holder and can only be brought into contact at one particular point of the holder with the surface to be worked, this working point being so designed that always only a limited depth of penetration of the tool is possible or a definite chip removal takes place.

On the drawing the instrument is illustrated in two different constructional exam- Figure 1 shows the instrument of the first example with its holder, in longitudinal section, Fig. 2 a side view of the milling tool with the protecting head in which it is embedded, Fig. 3 a head view of the instrument, and Figs. 4 and 5 an inside view of the two parts of the divided protecting head.

While the constructional form l5 shows an instrument which can be mounted on a dental hand piece in such manner, that the shaft of the milling tool is gripped and driven by the spindle of the hand piece, the instrument shown in Fig. 6 half in elevation and half in section is designed directly as a hand piece for connecting up to the flexible shaft and is distinguished from the fiton instrument shown in Figs. 1-5 by the fact that in its lower part it has a separate shaft which is connected with the flexible shaft by a so-called slip oint.

The instrument consists mainly of the holder a, the head dd and the milling tool 6, rotatably mounted in said head. To ob tain a protecting head of minimum size that does not hide the operation field, for tools with rounded or forward sloping profile a division of the holder head is necessary in order to permit ofinserting the cutting tool in the latter, Figs. 25. The milling tool, for example elliptic in shape, is bedded by means of a hardened bush 6 in the holder head, consisting of the two shell like parts d, d and held together by screwing it into a threaded opening of the holder a.

The head part (5 is provided with a recess cZ which exposes a portion of the tool I) and thus enables it to attack the skin. Said recess is so dimensioned that the milling tool 6 only penetrates to a defined depth into the part to be worked, thus avoiding the possibilities of injuries. ed on the handpiece as indicated by dot and dash lines, which with its spindle drives the shaft 6 of the tool I). The side cut away parts cZ in-the upper part d of the holder head serve for the passing of the chips.

I claim In an instrument of the character described in combination, a holder, a divided head, said divided head consisting of two shell like parts, said shell-like parts being screwed into a threaded opening in said holder, and held together, and a milling tool rotatably mounted and partially enclosed in said divided head-parts, said divided head having a cut away part to expose a portion of said milling tool.

J OSEF HOLZ.

The holder a is insert- 

